Hello, I have a question about practice regarding filter application to a peripheral or central venous access device for pt's with PFOs. Is there any reliable evidence in regards to how much air it would take to negatively affect a patient, and how necessary are filters? I have read somewhere that >3 mL air would need to be injected into the bloodstream to potentially cause fatal effects. Some institutions only apply filters for medications & TPNs and do not address PFOs/filter application. Other institutions are highly vigilant in this practice and enforce filters for any patient with a documented history of a PFO. What happens to patients who have PFOs that aren't documented? I'm wondering if there is even any significant research data available to support filtering these patients or if outcomes would be the same without filter application. Thank you!! -Jenny Jones, RN, VA-BC
There are recommendations for filtering all infusions in patients known to have PFO, but I can't search for them now as we are finalizing the INS standards. If I come across anything I will post it. There is no minimum or maximum amount of air confirmed to cause a venous air embolism. Studies are conducted on animals and extrapolated to humans. Even microbubbles is known to lead to pulmonary hypertension, although this is not seen as a catastrophic event like VAE is. Undiagnosed PFO patients would have air and particulate matter travel from the right heart to the left heart, bypassing the lungs, and out to the body, usually the brain.And yes, this has been an issue in a couple of lawsuits involving VAE that I have seen. Lynn
Lynn Hadaway, M.Ed., RN, BC, CRNI
Lynn Hadaway Associates, Inc.
126 Main Street, PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861